Lang's new Mack toy carrier

I found the 12v power pack I bought for my tipping trailer didn’t have a large enough tank to fully extend the ram.
Something to consider or make Enzed even more wealthy and run double acting rams.

Lang, a hint to why Froggie Dog's cab may be so hard to tilt.
My mate bought an Acco with a big folding crane behind the cab. He went over it to get it roadworthy and had the same tilting problem. It has a pair of big coil springs, similar to those on car suspension struts under the cab. One spring was broken.
He took the spring out and welded it, replaced it and now the cab really is easy to tilt. A couple of weeks later, he found four car type suspension springs that a tenant had left behind and wished he had found them before he welded the spring!
If Froggie Dog has similar springs, check 'em and if you have a car coil spring lying around, try that.
Removing and replacing the spring is a two-person job. One person has to be shorter and more flexible than me, I am about your height. The second person only has to hold a spanner on top of the bolts from above the cab floor, while the smaller person works from underneath the truck.

Steve

You can see from below that drag of an object is caused by the turbulent flow over a sharp edge. As it leaves the object the air can not turn sharply enough around a square corner and breaks away causing turbulence which uses up huge amounts of energy. In aircraft, cars etc they alter the shape to make the air flow smoothly and stick to the surface as long as possible to leave the object with as little turbulence as possible.

The frontal area, say on a set of solid ramps is constant and in itself causes only limited drag. What causes the drag is the air leaving the sharp edges and resulting turbulence. So, if you want to create as much drag as possible you must have as great a length of sharp corners as possible. Looking at those aircraft drag brakes (to stop the dive bomber going into a supersonic dive when descending vertically) you can see they have hundreds of holes or on the other one hundreds of square rods between the frame. If they were solid plates they would have an edge length of say 20 feet but with the holes or square rods they have an edge length of 50 feet giving 2 1/2 times the drag.

Same thing with solid ramps and ramps with treads. That is why a truck carrying dozens of long pipes has much less drag if there is a tarp over the front. Most people would think it is better to let the air flow through but then you have many metres of square edges at the back, not just inside but between the pipes, as the air flows through all causing turbulence and drag.


Definition
Form Drag, also known as Pressure Drag or Profile Drag, is the drag caused by the separation of the boundary layer from a surface and the wake created by that separation. It is primarily dependent upon the shape of the object.

Description

Form Drag
In the upper figure of the diagram, the relative wind across a flat plate results in a leading edge stagnation point at the front of the plate that contains very high static pressure. The airflow attempts to maintain contact with the surface of the plate, but the streamlines are unable to follow the sharp angles which would be required to allow them to fill in behind the plate. As a result, they separate at the trailing edge of the plate leaving a low pressure wake area behind it. The pressure differential between the leading and trailing edges of the plate causes the plate to be pushed in the direction of the relative wind and retards forward motion. This is form drag.

To reduce form drag, aircraft surfaces which are exposed to the airflow of the relative wind are streamlined. The remaining figures of the adjacent diagram show how, as the streamlining is increased, the form drag is decreased.

Sooo how about using the deflectors from cab front to put each side of the flat plate (ramp)?

Probably increase drag as even more air is being pushed past the square edge of the plate giving more turbulence and drag.

Those deflectors are just that, to deflect the direction of the airflow close to the door to stop spray on the mirrors. The truck would almost certainly have less drag without them. They are just like putting your open hand out the window when you were a kid and nearly having your arm ripped off. When you had your hand nicely rounded your whole arm would float weightless in the wind so just like the deflectors it is taking energy to change the wind direction and give an up force to your hand.

Lang

Lang, you are our resident fly boy, can we expect you to redisign the ramps into wing or tail plane shapes gaining left and reducing drag...... ? Come on you can do this.

I already considered that but could not solve the traction problem of the truck having a full floating rear axle.

Lang

Lang the ramps on Lorry are way longer than yours and with just one spring on them they are an easy lift. Don't quote me on this but I think these types of springs come in differnet ratings to suit the application.

That’s right Cobber, I went to Haulmark way back when designing some low loader ramps.
Had two on each ramp, they were massive springs.
The pin up top was about 40mm diameter and we fitted a tube over that to reach the I/D of the springs, from memory about 65mm I/D.
In more modern times I helped the brother in law with his horse float springs. Two on the ramp and they were rolled from about 16mm bar.
Babies yet we still struggled with them, must be an age thing.

A quick search has Transparts Qld, out at Willawong so you could go for a chat/advise on ramp spring sizes.
Ph 32734155